a92cc71f65 Create impl_mul_assign and impl_div_assign macros (Shing Him Ng)
Pull request description:
The macros were called on type-rhs pairs that have an existing implementation of ops::Mul and ops::Div, respectively, that have an `Output` of `Self`
Not as many types as I would have thought, but most of the operations result in a `NumOpResult`, which can't be then assigned back to the variable.
Closes#4172
ACKs for top commit:
apoelstra:
ACK a92cc71f658771776557ea0a40d1d095d3b6d482; successfully ran local tests
Tree-SHA512: 30cfb077b9ba65af991eb17fa05ffc4a870c3f4ded746355d3a8577a71fe9a569588a882c2a936edcc9c88feede4d8bb1379a998e3f330894084a4e2fc434e6e
12cef1d16b